docs: def xf2rav(xform):
      """
      This routine determines the rotation matrix and angular velocity
      of the rotation from a state transformation matrix.
      http://naif.jpl.nasa.gov/pub/naif/toolkit_docs/C/cspice/xf2rav_c.html
  
      :param xform: state transformation matrix 
      :type xform: list[6][6]
      :return:
              rotation associated with xform,
              angular velocity associated with xform.
      :rtype: tuple
      """
      xform = stypes.toDoubleMatrix(xform)
      rot = stypes.emptyDoubleMatrix()
      av = stypes.emptyDoubleVector(3)
      libspice.xf2rav_c(xform, rot, av)
      return stypes.cMatrixToNumpy(rot), stypes.cVectorToPython(av)